Method of making dentures



July 1, 1947.-

C. LEVINE METHOD OF MAKING DENTURES Filed April 18, 1945 TAKINGIMPRE5$ION OF MOUTH TO FORM NEGATIVE FROM UCH NEGATIVE FORMING A FIRSTPO$IT\VE DIE FORMING A ME H WAX PATTERN ON 5UCH FIRST-DIE cAsTme AME-rm.MESH mass on sucH FIRST DIE USING SUCH PAW-FERN CAST METAL ME5H DASE wFROM SUCH NEGATIVE FORMING A ssooflo POSITIVE DIE REMOVING SUCH 585EFRO/Y1 fiu'cH FlRsT'DlE AND TRAHSFERRING SUCH BASE 'T'o THE SECOND DIEFbRmme A DEIHTURE usme sucH a sz AI'IO sucH SECOND DIE Cffcatzas LevineREMOVING ucH DENTURE ITH 9/165 INCLUDED FR M fiUCH szcorm on;

awe/whom abtowwg Patented July 1, 1947 T :QUNITED 'sT r s PATENT I orrcs Charles Levine, Detroit, Mich.

Application April 18, 1945, Serial No. 588,968

1 Claim.

This application relates to methods of manufacturing dentures.

The denture hereof is characterized by having as an integral partthereof, disposed against the tissue engaging surface of the denture, acast metal mesh base. For an understanding of the denture of thisapplication, reference will now be had to the appended drawing. In thisdrawing,

Fig. 1 is a flow diagram of the steps in the manufacture of the denture.

Fig. 2 is a transverse cross sectional view of the denture.

Fig. 3 shows the cast metal mesh base per se.

In the drawings, Fig. 1 is a flow diagram indicating the steps in themanufacture of the denture and their relationship to each other, whileFig. 2 shows the denture having a plastic plate i 0, teeth I I, and acast metal mesh base [2 on the upper or tissue engaging surface of theplate. lhe mesh openings of the base are filled with the plate materialbut otherwise the shape of the denture with the base therein is exactlythe same as the shape that the denture would have taken had it been madeaccording to conventional practice, 1. e., without the cast metal meshbase in it.

The manufacture of a denture with a cast metal mesh base in place on thetissue engaging surface thereof will generally follow the conventionalmethod of manufacturing of dentures with, however, slight variations. Inthe manufacture of dentures, it is conventional first to take animpression, a negative, and then to cast one or more positive dies fromsuch impression. In my method, I cast at least two duplicate positivedies, using both of them. At this point, however, my method takes on avariation from the conventional method, for at this point, I make on oneof the two duplicate dies a wax pattern of a cast metal mesh base to becast onto that die, and then I cast a metal mesh base from such patternonto that die. Both the forming of the wax pattern and the casting ofthe base from such pattern can be done according to techniques wellknown in dental laboratories. The casting may be by the well knownlostwax method, wherein the die and pattern are invested in a suitableinvesting plaster which is heated to vaporize and destroy the wax toleave a space into which the casting metal is poured to form the base.When the casting is completed the die and the investment are broken awayfrom the casting to leave the latter free. Then I transfer the completedcast metal mesh base to the other die, and from there on I proseed againaccording to conventional practice, fitting teeth in wax on the castmetal mesh base, now on the second die, then investing the model thusformed in plaster in a flask to form a mold, and then forming a plasticdenture in such mold around the teeth and the base to form the completeddenture with the cast metal mesh base in place in the denture.

The only novel structural element of my denture is the cast metal meshbase. This is cast from any suitable metal. One metal that I have foundsuitable in a chromium-cobalt-tungsten alloy which is sold by theNobilium Processing Co. of Chicago, Illinois, under the trade-markNobilium.

The cast metal base reinforces and strengthens the denture, minimizesthe danger of breakage, and also prevents warping of the denture.

In dental practice, it is necessary, from time to time, to relinedentures after they have been worn and used for a while to compensatefor the shrinkage of the gum or tissue. Relining simply means addingsufficient material to the tissue engaging surface of the denture tomake it conform to the shape that the tissue has taken after it hasshrunken away from the denture. A denture made with a cast metal meshbase in it, according to my invention, can be relined. However,

the cast metal mesh base improves the bonding between the relining andthe denture.

It is important to note that the metal mesh base herein disclosed iscast to a positive die, and thus accurately conforms to the tissueshape, reproduced in that die. In addition, the metal base, a goodconductor of heat, aids in curing the plate.

My invention may be applied to all sorts of dentures, to partialdentures as well as to complete dentures, to lower dentures as well asto upper dentures, etc. In all cases, the general shape of the castmetal mesh base will conform to the shape of the denture, regardless ofthe shape which the denture assumes, and because cast, the base willconform to the tissue shape reproduced in the die.

Now having described my denture and my novel method of making dentures,reference should be had to the-claim which follows.

I claim:

In the manufacture of dentures, the steps of casting two dies aspositive reproductions of the mouth portion for which the denture isbeing made, forming on one of such dies a wax pattern of a cast metalmesh base, casting on that die from that pattern a cast metal mesh basewhich by being patterned and cast on that positive die, is shaped toconform to the formation of the tissue of the mouth portion and is rigidand unyielding, removing that cast base from that die and transferringit to the other die, forming on that second die a denture, with thatcast base as a base, and with teeth in the denture.

CHARLES LEVINE.

REFERENCES CITED The following references are of record in the file ofthis patent:

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